I am about to graduate from high school and pursue my physics degree! Please help clear up these questions I have :)
Ok so I know about spectroscopy and how electromagnetic radiation causes electrons to gain more energy and move to a more excited state...emission absorption spectrums yada yada. I have a couple of questions however.
What makes an electron lose the energy it gains from the electromagnetic radiation? Why must it emit the photons and not simply just stay in the excited state? Is it an entropy problem or does it lose a certain amount of kinetic energy and the rest of the "gap" between energy levels is emitted out. That leads to my second question.
Do electrons emit the same radiation as it absorbed when it goes down the subsequent energy level? If so, doesn't that categorize it as a black-body?
Is thermodynamic entropy simply a mathematical problem...like statistical...or is there a physical reason for it? I apologize if that doesn't make much sense. In essence...why does entropy occur? I would assume it would just be math related to the statistics of a system...or maybe im totally off.
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Thats a tough one. Your right out of high school you say??
I cant answer your question completly but hopefully some of this info can help.
What makes an electron lose the energy it gains from the electromagnetic radiation?
From all our observation of the universes one of the things that always appears to hold is the fact that processes will always work in a way (without any external influence) which causes equilibrium. In thermodynamics we call that "spontaneity". Any process which results in spontaneity will cause an increase in entropy. This is in terms of macroscopic situations ( thermodynamics )but, it may or may not apply to electrons and their energy states. My hunch would be no. Because transitioning is not continuous ie..electrons transition in distinct energy jumps. Becasue there is no middle ground i would guess that changing energy states would result in something called a reversible process. In the case of a reversible process the entropy remains the same.
Do electrons emit the same radiation as it absorbed when it goes down the subsequent energy level? If so, doesn't that categorize it as a black-body?
Yes to the first part. Energy is conserved.
Blackbody is a body that absorbs all light. In this case i would say no. Because the electron does not absorb all incoming light. It only absorbs a specific wavelength.
Is thermodynamic entropy simply a mathematical problem...like statistical...or is there a physical reason for it? Entropy is mathematical in that it cannot be directly measured. It has to be interpreted fomr a simple mathematical ratio. On the other hand it is real and can be used to define the "state of a system. To define a substance thermodynamically you need to define the values of something called the "state variables" . One of the state variables is the entropy. NOTE: you only need to define 2 state variables.....EX: volume and temperature ; or Entropy and pressure etc..
Thermodynamics does not deal with the statistics of the system. The art that deals with of the statistics ...i.e the microscopic view with billions of billions of molecules is some called statistical mechanics...or in the beginner level..physics thermodynamics